IP-NETNS(8) Linux IP-NETNS(8)NAMEip-netns - process network namespace management
SYNOPSIS
ip [ OPTIONS ] netns { COMMAND | help }
ip netns { list }
ip netns { add | delete } NETNSNAME
ip netns identify PID
ip netns pids NETNSNAME
ip netns exec NETNSNAME command ...
ip netns monitor
DESCRIPTION
A network namespace is logically another copy of the network stack,
with its own routes, firewall rules, and network devices.
By convention a named network namespace is an object at
/var/run/netns/NAME that can be opened. The file descriptor resulting
from opening /var/run/netns/NAME refers to the specified network names‐
pace. Holding that file descriptor open keeps the network namespace
alive. The file descriptor can be used with the setns(2) system call
to change the network namespace associated with a task.
For applications that are aware of network namespaces, the convention
is to look for global network configuration files first in
/etc/netns/NAME/ then in /etc/. For example, if you want a different
version of /etc/resolv.conf for a network namespace used to isolate
your vpn you would name it /etc/netns/myvpn/resolv.conf.
ip netns exec automates handling of this configuration, file convention
for network namespace unaware applications, by creating a mount names‐
pace and bind mounting all of the per network namespace configure files
into their traditional location in /etc.
ip netns list - show all of the named network namespaces
This command displays all of the network namespaces in
/var/run/netns
ip netns add NAME - create a new named network namespace
If NAME is available in /var/run/netns/ this command creates a
new network namespace and assigns NAME.
ip netns delete NAME - delete the name of a network namespace
If NAME is present in /var/run/netns it is umounted and the
mount point is removed. If this is the last user of the network
namespace the network namespace will be freed, otherwise the
network namespace persists until it has no more users. ip netns
delete may fail if the mount point is in use in another mount
namespace.
ip netns identify PID - Report network namespaces names for process
This command walks through /var/run/netns and finds all the net‐
work namespace names for network namespace of the specified
process.
ip netns pids NAME - Report processes in the named network namespace
This command walks through proc and finds all of the process who
have the named network namespace as their primary network names‐
pace.
ip netns exec NAME cmd ... - Run cmd in the named network namespace
This command allows applications that are network namespace
unaware to be run in something other than the default network
namespace with all of the configuration for the specified net‐
work namespace appearing in the customary global locations. A
network namespace and bind mounts are used to move files from
their network namespace specific location to their default loca‐
tions without affecting other processes.
ip netns monitor - Report as network namespace names are added and
deleted
This command watches network namespace name addition and dele‐
tion events and prints a line for each event it sees.
EXAMPLES
ip netns list
Shows the list of current named network namespaces
ip netns add vpn
Creates a network namespace and names it vpn
ip netns exec vpn ip link set lo up
Bring up the loopback interface in the vpn network namespace.
SEE ALSOip(8)AUTHOR
Original Manpage by Eric W. Biederman
iproute2 16 Jan 2013 IP-NETNS(8)